Investigating the effect of grain interaction during plastic deformation of copper Original Research Article

By diffraction of high-energy synchrotron X-rays, the variance of the axial lattice strains of individual grains is measured during tensile loading of a weakly textured copper polycrystal. Peak profiles are measured for {4 4 0} reflections arising from 20 bulk grains, all of which are at least one average grain diameter below the surfaces within a 0.2-mm thick specimen. The reflecting lattice planes are all perpendicular to the tensile axis. The variance in lattice strain between grains can therefore be attributed to differences in the boundary conditions imposed by the different sets of neighboring grains. The results are compared to finite-element modelling (FEM). Up to the highest applied strain of 2%, the experimental and FEM values are in fair agreement and the standard deviations may be roughly approximated as 6% of the average axial lattice strains.